Surveyor s instrument



(No Model.)

J. R. HANLON.

SURVBYORS INSTRUMENT.

No. 430,015. PafeatedJune'4 10, 1890.

v UNITED STATES PATENT OFFICE.

JOI-IN RUSSELL IIANLN, OF PENNINGTON, NEV JERSEY.

SURVEYORS INSTRUMENT.

SPECIFICATION forming part of Letters Patent No. 430,015, dated June 10,1890.

Application .filed February l5, 1890. Serial No. 340,567. (No model.)

To all whom it may concern:

Be it known that I, JOHN RUSSELL HANLON, a citizen of the United States,residing at Pennington, in the county of Mercer and State of New Jersey,have invented certain new and useful Improvements in SurveyorsInstruments; and I do hereby declare the following to bea full, clear,and exact description of the invention, such as will enable othersskilled in the art to which it appertains to make and use the same.

The invention relates to improvements in the stands of theodolites andiield-transits, the object being to provide means whereby the telescopecan easily have its height adjusted after the instrument has beenleveled; and it consists in the construction, arrangement, and novelcombination of parts hereinafter described, illustrated in the drawings,and particularly pointed out in t-he appended claims.

In the accompanying drawings, in which similar letters of referencedesignate corresponding parts, Figure l represents a perspective view ofthe top or head of a theedolite or transit stand embodying theinvention. Fig. 2 represents a central vertical section thereof.

the plates are leveled. The leveling of the,

plates frequently changes the height, so that it is sometimes necessaryto readj ust the instrument several times before it can be leveled atthe desired height. By means of my invention this is obviated, as thetelescope has its height accurately adj usted after being leveled.

Referring to the drawings by letter, A designates the limb or upperplate ofthe instrument, B the lower or leveling plate, C the spindlerising from the plate B, and D D the ad justing-screws, all of ordinaryconstruction.

E is a boss depending from the limb or upper plate and recessed at e toreceive the upper end of the spindle, which is tapered slightly upwardfrom the lower plate B. The said boss has its lower portion e threadedexternally and reduced in diameter below the,

circumferential shoulder e2.

F is a cylindrical sleeve fitting on the spindie below the said boss andturning thereon. G is a clamping-collar surrounding said sleeve at itslower end above the plate B, and g is a clamping-'screw engaging insuitable openings in the lugs or ears g g of said collar, in order tobind the sleeve, when necessary, 'on the spindle and prevent it turningthereon.

The outer surface of the sleeve F above the clamp G is screw-threaded toengage the similarly-threaded interior surface of an outer cylindricalsleeve I-I, the upper end of which screws upon the threaded part e ofthe boss E and abuts against the shoulder e2.

The sleeve H is provided with the longitudinalv slits or slots h h,extending upward from its lower end to a suitable height, and preferablythree in number and equidistant.

I .is a clamping-collar, similar to the collar G, surrounding the sleeveH over said slits, and t is a clamping-screw engaging in suitableopenings in the ears or lugs i of said clamp to bind the outer sleeve onthe inner sleeve and prevent it from rotating thereon. The slits hin theouter sleeve enable the clamp I to bind said sleeve on the inner sleeveand prevent it turning thereon. y

When the clamp G is loosened, the instrument can be turned laterally t0any desired angle.

The operation of the invention is as follows:

'Tighten the clamp G to prevent the inner sleeve from turning on thespindle. Then loosen the clamp I and screw the outer sleeve up to anydesired height on the inner sleeve. Then tighten the clamp I and loosenthe clamp G, and the instrument may then be turned laterally to anydesired angle, the height of the telescope remaining unchanged. Thedevice is of simple construction, and by it much trouble and time may besaved in the use of the theodolite and transit.

I-Iaving described my invention, I claiml. The combination of the outerinternallythreaded sleeve with its upper end attached to the limb orupper plate, the inner externally-threaded sleeve engaged within vtheIOC outer sleeve, and a suitable clamp by means of which the ou tersleeve may be prevented from turning on the inner sleeve, substantiallyas specified.

2. The combination of the outer internallythreaded sleeve H, providedwith longitudinal slits extending upward a suitable dis-` tance from itslower end, the limb or upper plate attached to the upper end of saidouter sleeve, the inner externally-tln'eaded sleeve engaging in theouter sleeve, and the clamping-collar surrounding the outer sleeve overthe slits, substantially as specified.

The combination, with the spindle rising from the lower plate, the innerexternallythreaded sleeve rotatable on the spindle, and theclamping-collar surrounding said sleeve below its threaded portion andjust above the lower plate, of the outer internally-tlu-eaded sleeveprovided with slits extending upward a suilicient distance from itslower end, the upper plate secured to the upper end of the outer sleeve,and the clamping-collar surrounding the outer sleeve over the slits,sub-

